Northwestern University, the 20th-ranked college football team in the nation, won’t win a national title on the field this year. But the Wildcats are first in the classroom, according to the “Academic BCS,” the New America Foundation’s annual academic performance rankings of the top-25 college football teams.

Northwestern’s top finish is not surprising. But the New America Foundation’s second-best academic team, Northern Illinois — which finished ahead of schools like Notre Dame, which will play for the national championship on Jan. 7 against Alabama, and Stanford — is a more curious case. The Huskies, who earned a bid to the Jan. 1 Orange Bowl, are a surprise both on and off the field.

How did Northern Illinois finish so high? The New America rankings are not just based on raw statistics like graduation rates or the NCAA’s Academic Progress Rate, which indicate how well a team is keeping its players on track to graduate. If that were the case, a school such as Notre Dame, which graduates 83% of its players, according to federal data, would finish well above Northern Illinois, which has a 66% rate.

Instead, the New America Foundation bases its rankings on several factors: how a football team’s graduation rate compares to that of the school’s overall male student body, how a team’s black-white graduation gap compares to the male black-white graduation gap in the general student population, and the spread between a football team’s black graduation rate and the school’s overall graduation rate for black men. “Our formula is the only one out there that puts these statistics into context,” says Alex Holt, an education researcher at the New America Foundation. (New America’s formula gives less weight to a school’s Academic Progress Rate, which it considers a less rigorous test, than actually graduating).

So Northern Illinois scores major points because football players graduate at a higher rate (66%) than the Northern Illinois student body at large (51%). At Northern Illinois, 72% of white players graduate, while 63% of black football players graduate: that’s a nine-point difference. In the general population, 56% of white male students at Northern Illinois graduate, compared to 30% of black male students. That’s a 26-point difference for the student body, compared to a nine-point difference for the football team: again, New America credits Northern Illinois football for outperforming the rest of the school. Also, while 63% of Northern Illinois’ black football players graduate, just 30% of black male students graduate overall. That 33-point difference propels the Huskies to the top of the standings.

On the flip side, look at the team from Michigan, a school with a strong academic reputation, yet finishes near the bottom of these rankings. While Michigan graduates 88% of its students, only 59% of Wolverine football players get their diplomas. While the black-white graduate gap on the football team is only four points worse than black-white gap for all male students, just 47% of Michigan’s black football players graduate, compared with 70% of Michigan’s black male students overall.

(For more details on each school in New America’s study, click here for a graphical representation of the results.)

Almost all education rankings are imperfect, and New America’s research is no different. In order to make comparisons with overall graduation rates on a given campus, for example, New America Foundation uses federal graduation rates in its data. College athletic departments have criticized these rates for understating an athletic team’s performance, since players who transfer out of a school and pursue a degree elsewhere, or leave early for the pros, count against them. To account for athlete mobility, the NCAA came up with the “graduation success rate” (GSR), which credits teams for graduating incoming transfers, and doesn’t penalize them for having players transfer out or pursue the pros. For almost all teams, the GSR is higher than the federal rate. But there is no GSR for the rest of the student body, so New America uses the federal rate to make comparisons.

Aside from the baseline numbers, you can certainly question a methodology that gives more credence to campus context than raw performance, which puts Northern Illinois, with its 66% federal graduation rate for football, above Notre Dame, at 83% (Northern Illinois has a 83% GSR, while Notre Dame’s GSR is 97%). But no matter how you slice the numbers, as we go into bowl-game season, the study reminds us of the shortcomings of college sports. For 19 of the top 25 football teams — or 76% — their federal graduation rates are lower than those of the overall student population. On 22 of the top 25 college football teams — or 88% — more than 30% of the players fail to graduate. Using the more generous, and probably fair, measure — the GSR — 15 out of the top 25 college football teams (60%) fail to graduate more than 30% of their players.